The \({D=2}\)  geometry à la Witten [1]} is characterised by
\({{\rm d}}s^{2}={{\rm d}}y^{+}{{\rm d}}y^{-}/F\)  with \({F=-1+y^{+}y^{-}/l^{2}=\frac{F}{|F|}e^{-2\phi }}\) .
It solves (REF ) when \({\Lambda _{\scriptscriptstyle {\rm {DFT}}}=-\frac{2}{l^{2}}}\) . From \({R=-\frac{4}{l^{2}F}}\) , the hyperbola, \(y^{+}y^{-}=l^{2}\) , corresponds to a curvature singularity. We stress that though the \(H\) -flux is trivial in two dimensions, the \(B\) -field still plays a crucial role in making the generalised metric free of coordinate singularity (REF ).
